Research
Variations in the Concentration of CO2 in Associated Gases: Evaluation of the Performance of a Conditioning Process with Turboexpander
Herein we disclose an evaluation of the performance of a Turboexpander unit for the conditioning of associated gasses with different CO2 contents. The performance evaluation was carried out by the comparison of the results from a simulation in Aspen Hysys v10 with the specifications established in the national gas transportation policy for natural gas (RUT). The Turboexpander unit was designed for the conditioning of an associated gas defined by the scenario of medium production for the Valle Medio del Magdalena, according to the prospects of the Mining and Energy Planning Unit (UPME). The conditioning unit considered the sections: stabilization, sweetening, dehydration, and separation by distillation. Similarly, the range for CO2 content variation was defined between 3 - 12% mol, based on enhanced recovery (EOR) pilots of air injection and CO2 injection. The results of the simulations showed an adequate performance of the Turboexpander unit for the conditioning of associated gasses with up to 6% mol of CO2 contents, fulfilling the quality parameters of the RUT. Likewise, the simulation results showed that the temperature profile in the absorption tower (sweetening section) changed when gasses with CO2 contents greater than 6% mol were treated. This temperature profile change appeared to be responsible for poor CO2 removal performance. The foregoing would suggest adjustments for the sweetening section or a shift of the respective technology in order to fulfill the quality parameters specified in the RUT.
